Just curious about something concerning venting and my take on FAK/OAK exterior Termination

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SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan
I keep seeing venting installs with a cone shaped end on them (pointing downward and straight out of the stove), what is with that? I don't much care for it but I keep seeing it in pictures posted on here? Looks to me like a cheap out on termination as well as a nice 'home' for summertime pests.

Secondly. I much prefer the US Stove Fresh air intake kit, even if the fresh air intake is integrated into the wall thimble because the US Stove exterior cover comes screened for bugs and the stamped in vent holes all point downward and I use it on both my house stove and soon the shop stove as well. Not expensive either and comes with both the exterior cover as well as an interior plate that makes it look 'finished' and it comes with the expandable foil hose and worm clamps to install everything. 20 years on my house OAK and never an issue with bugs or the intake hose.
 
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Mt Bob

Minister of Fire
Oct 31, 2013
3,630
park county montana
They are called jet or vortex caps. They work especially well on days that the wind hits that side of a house. They also push particulate matter farther away. They generally have a anti bird screen in them.
I think,from what I have seen,people purchace a pellet stove used or from a big box store,even farm store, and do not even know aboutOAK, until they come to a forum like this, but they have already purchased a flue kit, and those types of places do not know "best practices". Also,very rare to hear about an insect problem, in flue or intake air,probably because they are so sensitive to odors, and the wood burning smells keeps them away. Birds are another story.
 

SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan
Birds are another story.
The unit I bought used I got the venting as well, owner was going to throw it in the rubbish so I asked and got it and it has a very nice bird nest inside. I'm going to put a chicken wire screen on the outlet. That should eliminate that issue.

I would think that insects and yellow jackets and such would move into the OAK if not screened like the USSC OAK is. Besides it looks finished on the inside as well as the outside and comes with everything necessary to install it, even the screws.

That 'vortex' end to me looks very cobbly. Reminds me of an inverted ice cream cone. Not something I'd use.
 
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Mt Bob

Minister of Fire
Oct 31, 2013
3,630
park county montana
Jet caps on the flue have been around many years,and have never heard or seen a complaint, even on stove forums like this. They are a logical solution to a problem. I actually think they look more professional.. Just as I have never seen or heard of an insect problem on/in fresh air vents, I figure it is from the smell/odors. Just as you almost never hear of insects in a direct vent NG or LP intake,and there are many millions of them.
 
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SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan
Jet caps on the flue have been around many years,and have never heard or seen a complaint, even on stove forums like this. They are a logical solution to a problem. I actually think they look more professional.. Just as I have never seen or heard of an insect problem on/in fresh air vents, I figure it is from the smell/odors. Just as you almost never hear of insects in a direct vent NG or LP intake,and there are many millions of them.
Had them invade the exhaust on my RV and had to purchase aftermarket screens. A continuing issue on RV's. Yellow Jackets will nest about anywhere they can gain access. Heck, they moved into one of my wife's wind chimes this year and they are nasty aggressive little buggers that will stitch you in a second. Have to wait for dark and then eradicate them because they cannot see in the dark. Nothing can get into the exterior OAK intake of the USSC kit. It has fine mesh screening inside the box.

The bigger the nest got in the wind chime, the duller the chime sound got...lol
 
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Mt Bob

Minister of Fire
Oct 31, 2013
3,630
park county montana
Yes,it happens a lot on limited use RV's. Fine screens on stove intakes are known to frost over,even totally restricting airflow, especially in high humidity areas. But,if it is part of the flue exit,never heard of it happening, as there is heat there.
 

SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan
Yes,it happens a lot on limited use RV's. Fine screens on stove intakes are known to frost over,even totally restricting airflow, especially in high humidity areas. But,if it is part of the flue exit,never heard of it happening, as there is heat there.
Never had that issue as we only use it in the summer. In fact, it's sleeping presently inside
 

Ocelot

Burning Hunk
Dec 27, 2010
102
Hudson Valley, NY
I've had the screen on my fresh air intake clog up a couple times over the years during a snowstorm. Basically, windblown snow caked on the screen and the flame got lazy. It only happened about 3 times in ten years since it takes specific circumstances. The first time it happened, it took me a bit to figure out why I had the lazy flame. My new fresh air intake I custom made with a round stainless steel RV screen so I doubt I'll see it happen again.

Ray
 
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mtnbiker727

Burning Hunk
Mar 11, 2019
219
PA
My stove was dealer installed and they didn't do an OAK (or an appliance adapter for that matter), and only recommended an OAK for modern houses that are insulated tight. After coming on here and realizing I got poor service, I talked to another dealer a little farther away and got the same exact message from him. Now that I know what I know, I think they're wrong. I don't understand why they. Do they think they're saving the customer money?

When we get to our permanent home, I will set up an OAK.
 

Ocelot

Burning Hunk
Dec 27, 2010
102
Hudson Valley, NY
I think what they mean by new tightly sealed houses is it might make it harder to for the stove to get full airflow. But they are missing the part where in a not so sealed house, the negative pressure caused by the stove sucking in air and blowing it out the vent, also means it's going to suck cold outside air into the room from around window seal cracks, door seals, etc. That's not to mention without the OAK the stove is taking the heated room air and blowing it out the vent as well.
 

SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan
Makes no sense to me at all. I actually had a chance to work for a local company that sold biomass stoves that wanted me as an installer service man. I passed. Got way too much to do as it is. Would cut into my hunting time....lol
 
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Washed-Up

Minister of Fire
Nov 5, 2011
882
Kananaskis,Alberta, Canada
I’ve seen jet caps before and had no idea what made them special, after MtBob mentioned it above I had to look up a diagram, they’re pricey but are a decent looking concept

B8F48094-3E25-479B-B90E-4E329329A415.jpeg
 
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Mt Bob

Minister of Fire
Oct 31, 2013
3,630
park county montana
I’ve seen jet caps before and had no idea what made them special, after MtBob mentioned it above I had to look up a diagram, they’re pricey but are a decent looking concept

View attachment 285464
That is a fancy one. Most of us just use a cap that is tapered smaller at the outlet, accomplishes the same thing, by speeding up the air.
dura-vent-pelletvent-pro-round-horizontal-rain-cap-with-screen-for-vent-pipes-with-a-3-inch-inner-diameter-3pvp-hrc-69.gif
 
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Washed-Up

Minister of Fire
Nov 5, 2011
882
Kananaskis,Alberta, Canada
Technically it’s increasing pressure by restricting the flow to push it further away but I understand what you meant